There's only really one good controller for the CDi and it's bloody expensive. I only have one, so I opened it up, made a note of everything and set about replicating the circuit board. The idea was that this way I could make as many as I want and use "donor" controllers to wire them to. Obviously I normally use controllers I really like - Saturn, Mega Drive....In this case a Mega Drive like plug & play system controller.

It's pretty much just pictures at the moment, but I'll have more info up eventually.

Pin 18 is for up, so I later wired this to a SPDT switch (middle) then wired C and Up on the D-Pad to either end so that if Up = Jump in a game you can use the C button instead.

It's been a while...I think I have some files somewhere, I'll have to look for them. I did actually make a Mega Drive to CD-i controller adapter too. I just ran out of money trying to make more and never got back to it.